For some time now I have regularly writhed, inwardly howled, and, even at moments on trains when the onslaught was at its most merciless, clapped my ancient hands over my ears at the constant reiteration by young people addressing their friends or yabbering into their mobes of the once inoffensive word "like". "I was, like ... " they keep saying, a formula which has now superseded "I went ... " as a replacement for the boring traditional form "I said". Until a few days ago, I thought of this practice as unpardonably careless and slovenly. Then, while reading the works of Thomas Babington Macaulay, I came to see it was justified - even admirable.

One has to worry about Macaulay when, for instance, he writes in his account of the battle of Sedgemoor, that the king's commander, the odious Louis Duras, Earl of Feversham, heard firing, got out of bed, adjusted his cravat, looked at himself in the glass, and went out to see what his men were doing. How did Macaulay know about the tinkering with the cravat? Had Feversham's batman noted it down in a diary? Macaulay's chief delight was in telling a story, and sometimes he could not resist the temptation to slip in a detail or two which more rigorous writers would shun. There are conversations in his pages which can surely not have been documented. What he gives us are the words that, in his judgment, the protagonists ought to have used; or to put it another way, that Macaulay himself would have used had he been one of them. In the confrontation, for instance, in 1688 between James II and the recalcitrant bishops, did the king truly protest, as Macaulay reports, "this is mere chicanery"? (Chicanery is a favourite Macaulay word; but was it one of King James's?).

He is not alone, of course, among writers on deeply important matters in taking such liberties. Consider the familiar account of the Oval test match of 1902 in which, against all expectations, England beat the mighty Australians. Australia, as readers will no doubt remember, batted first, and made 324, Hirst of Yorkshire taking five wickets for 77. England responded with a mere 183. But then, thanks to the bowling of Lockwood of Surrey, Australia's second innings brought them only 121 runs, leaving England needing 262 to win. What principally turned the outcome for England was the innings of Jessop of Gloucestershire, who made 104 in just 77 minutes. And without any sixes - to score a six in those days you had to hit the ball clean out of the ground. Yet the game was still in the balance when Hirst was joined by England's no 11 batsman, his Yorkshire colleague Rhodes. Hirst was undaunted. "We'll get them in singles, Wilfred," he is said to have told him.

Did this conversation ever take place? Rhodes denied it; Hirst said he could not remember. Later it was widely believed that this line was the invention of the legendary Guardian cricket writer Neville Cardus, who'd attributed to Hirst the words which he, Cardus, would like him to have used in such circumstances. How much better a service it would have been to historical accuracy if Cardus had said: "Hirst was, like, we will get them in singles"; or if Macaulay had written: "the king was, like, 'this is mere chicanery'."

So, far from being an exercise in the slovenly, "I was, like ...", I am now persuaded, is a demonstration of rigour. What the speaker who uses this formula is essentially saying is: "I cannot vouchsafe beyond peradventure that the information with which I am about to present you is truly authentic; but here at least is the essence of what I believe I averred at the time."

What a shame that it is now too late to acquaint Lord Macaulay with this valuable usage. It might have transformed his historiography. It would certainly have radically altered his epic poetry. He may have been safe enough in asserting that Lars Porsena of Clusium swore by the nine gods that the great house of Tarquin should suffer wrong no more. But soon he goes on to claim: "Then out spake brave Horatius, / The Captain of the gate: / "To every man upon this earth / Death cometh soon or late. / And how can man die better / Than facing fearful odds, / For the ashes of his father / And the temples of his gods?". Yet these noble sentiments are unlikely to have been noted down by some passing reporter. "Then brave Horatius was, like ..." would surely have served posterity better.